Electrical antenna control circuit



April 19, 1960 w. K. JENSEN 2,933,597

ELECTRICAL ANTENNA CONTROL cmcurr Filed Oct. 24, 1956 INV TOR ATTUP/VEK tend or retract. .on-off switch 12 for turning on the receiver, which switch ,is directly connected to the storage battery 14 of the vehi- A 2,933,597 Patented Apr. 19, 1960 ELECTRICAL ANTENNA CONTROL CIRCUIT William K. Jensen, Royal Oak, MiclL, assignor to General Motors Corporation, Detroit, Mich., a corporafion of Delaware Application October 24, 1956, Serial No. 617,970 '4 Claims. (Cl. 250-16) This invention relates in general to radio apparatus and particularly to specific means for causing a retractable antenna to be extended automatically when the radio receiver is turned on and to be retracted into a housing when the radio set is deenergized. Particularly in installations on vehicles, projecting antennas offer a hazard from the standpoint of breakage. The outer contours of automotive vehicles are currently very smooth and any object projecting therefrom detracts from the appear ance as well as being located in a position where it may contact passing objects and be broken. During periods when the radio in the vehicle is not operated, the antenna is of no practical use and could much better be stored in a protected and out of sight location.

It is therefore an object in making this invention to provide means associated with a power driven antenna to automatically cause the same to be extended when the radio receiver is energized and to be withdrawn into its casing when the radio receiver is turned off.

Currently, power driven antennas are used to a relatively large extent for automotive vehicles. The antenna is extended and retracted by theme of an electrical motor capable of driving in two different directions. The control system disclosed herewith is adapted to be associated with such an electrically driven antenna.

With these and other objects in view which will become apparent as the specification proceeds, my invention will be best understood by reference to the following specification and claims and the illustrations in the accompanying drawing, in which:

Fig. 1 is a schematic diagram of a control circuit for a power driven antenna embodying my invention.

Fig. 2 is a circuit diagram of a modified form of control circuit embodying my invention in which the motor current does not have to pass through the on-oif radio switch, and

Fig. 3 is a vertical sectional view through a control relay of my-design embodying a manual override.

Referring now more particularly to Fig. 1, there is diagrammatically shown therein an electrically operated antenna 2 having electric motor coils 4 and 6 for driving the antenna either up or down respectively. A vertically traveling rod or shaft 8 is driven by the motor and forces the telescopic sections of the antenna to ex- The radio receiver lfl has a standard cle for power. A sensitive control relay 16 is provided .which has one stationary contact 18 and a movable contact 29 associated therewith, the latter being moved by v energization of a control coil 22 to separate the contacts.

The on-ofi switch 12 has a movable portion connected directly to the battery 14 and a stationary contact 24 connected through line 26 with one'terminal of the sensitive relay coil 22, the opposite terminal of which is grounded. Stationary contact 24 is likewise connected jithrough line 28 with a movable switch arm'30 of a map over center switch 31 which remains in its last operated position and is thrown by projections 34 and 36 on the antenna operating shaft or rod 8 engaging operating arm ,32 of electrical insulating material. Movable arm 30 of the switch 31 is adapted to engage stationary contact 38 when in its upper position. Contact 38 is connected through line 40 to one terminal of the field winding 4, the other terminal of which is grounded. Movable snapover switch arm 30 likewise carries in insulated relation, a contact 42 which is connected through line 44 with stationary contact 18 of the sensitive relay 16. Contact 42 on arm 39 is adapted to move into engagement with stationary contact 46 when the switch arm 30 is thrown over center to its lower position by movement of the actuating arm 32. Contact 46 is connected through line 48 with one terminal of field winding 6 of the motor, the other terminal of which is grounded. Movable contact 20 of the sensitive relay 16 is connected through line 50 with the positive terminal of the battery 14.

In the operation of this circuit, when it is desired to use the radio receiver 10, the on-oif switch 12-24 is actuated. This turns on the radio receiver 10 and at the same time completes a circuit to the motor field winding 4 to cause the antenna to be extended. This circuit is as follows: from the positive terminal battery 14, switch arm 12, contact 24, line 28, movable arm 30, contact 38, line 49, winding 4 to ground. The motor will therefore be energized to run in a direction to extend the antenna until projection 36 on the rod or shaft 8 comes in contact with the actuating arm 32 of the switch. This pressure pushes the arm 32 upwardly and when it reaches a certain critical point, arm 30 will quickly snap down, breaking contact with contact 38 and causing insulated contact 42 to engage stationary contact 46 and to remain in that position. This opens the circuit to the motor winding 4 and the motor stops. This conditions the circuit for energizing winding 6 by closing switch 42-46. This circuit is however open at contacts 2018, so that the antenna remains in its upper or extended position for radio reception. The'means for keeping these two contacts 20-18 open, is the relay coil 22, which was energized simultaneously with the closing of the on-oif switch 1224 through an obvious circuit. As long, therefore, as the radio remains energized, the antenna will remain in its extended position.

However, when the driver turns off the radio, opening switch 1224, relay coil 22 becomes deenergized and contact 20 may now engage contact 18 completing a circuit to the retracting winding 6 and the motor therefore retracts the antenna bringing it down within its housing until projection 34 engages the end of arm 32 carrying it downwardly to again cause a snap-over center action .to bring arm 30 back up to its position as shown. When this occurs, the circuit to the retracting winding 6 is broken and that to the extending winding 4 completed, ready for the next closure of the on-off switch of the radio receiver. It is to be noted that in Fig. 1 the current to the extending motor winding 4 passes through theon-off switch of the radio receiver and since this is a somewhat larger current than this switch was normally designed to handle, it may cause the life of the switch to be shortened.

Fig. 2 shows a modified form which no motor 'field current passes through the radio on-off switch. Simment with stationary contact 69.

line 52 to one terminal of the control relay 54 which is connected through the frame 56 to an armature 58. Armature 58 moves between two stationary contacts 60 and 62. Contact 60 is connected through line 64 to contact 42 insulatedly carried by snap-over center arm 30 and contact 62 in a similar manner is connected through line 66 with arm 30. Switch arm 3%) engagm stationary contact 38as in Fig. 1 which is directly connected through line 40 to one terminal of extending winding 4. Stationary contact 46 is connected through line 48' to one terminal of the retracting winding 6. The positive terminal. of the battery 14 is connected through tie line 68 with stationary contact 24 of the on-ofli radio switch and movable contact 12 of that switch is connected through line 70 to one terminal of the relay coil 72 of It. now the operator turns on the radio receiver and closes the on-ofi switch 12-24, coil 72 is energized through an'obvious circuit. It therefore attracts armature 58 pulling it down and breaking contact with stationary contact 60 and engaging stationary contact 62. A circuit is now completed to the extending motor winding 4 to raise the antenna. This circuit is as follows: battery 14, line 52, bracket 56, armature 58, contact 62,.line 66, switch arm 30, contact 38, line 40 and winding 4 to ground. Winding 4 is then energized and extends the antenna until the switch operating lug 36 engages the snap-over arm 32 to cause arm 39 to move over into engagement with the lower contact 46. This opens the circuit to the winding 4*and the antenna remains extended as long as the radio set is on. When the radio set is turned oflf by opening switch 12-24, relay coil 72 is deenergized and armature 58 moves back into engage- This now completes the circuit through switch 42-46 to the retracting winding 6 of the motor driven antenna and the antenna is retracted until operating lug 34 engages and moves the arm 32 downwardly to snap the arm 30 back up into the position shown. This opens the circuit for the winding 6 and the motor stops. M It is obvious that in'this instance no motor field winding current passes through the on-ofi switch but it is controlled completely by the sensitive relay switch '54..

Under some circumstances the operator may desire to obtain excessive height in the antenna for operation in remote rural areas. An additional manual override switch is therefore provided. This switch includes a movable arm 74- which engages the stationary contact 76. Contact 76 is directly connected to line 66 and movable arm 74 to line 40. This switch shunts the snap-over center switch 31. Therefore at any time that the radio is on and the antenna has been raised to the limit position determined by the location of the lug 36, the operator may by closure of switch 74-76 energize the winding 4 to extend the antenna further.

Figure 3 discloses a mechanical form of relay-manual override switch in which through manual operation the antenna may be retracted to any desired height. In other words, with the antenna control system such as "shown in Fig. 1, if the operator desires to retract the antenna to some intermediate point between the upper andv lower. limits as determined by the lugs 34 and 36, suchiazdevice' as that: shown in Fig. 3 maybe used. A casing 80 enclosesthe sensitive relay which consists of fixed contact 18, movable contact 29, and sensitive relay coil.;22,, these 7 elements being connected into the circuit as shown in Fig. 1. If, however, .some mechanical means a erusedi c osethesw tching-20,, the retra ti gswi ing 6 will be energized. Such a means could take the form of a plunger 8-2 lightly spring biased downwardly by spring 84 into engagement with the spring switch arm 20 to prevent chatter but not strong enough to force 20 down when coil 22 is energized to hold it up. Manual pressure on the end of plunger 82 will force contact 20 down into engagement with stationary contact 18completing the circuit to the retracting winding 6, and asilong as the operator holds'the plunger down, the motor will retract the antenna until the limit switch 31 is actuated.

I have, therefore provided automatic means for extending or retracting the antenna with radio operation together with override means either for obtaining excessive height for rural operation or permitting a partial retraction at will.

I claim:

1. In radio apparatus having asource of electrical power and an energizing switch connected to said source of power and radio apparatus to control the latter, dual winding power driven extensible and retractable antenna means, limit switching means including two separate switching means that remain in the position to which it was last actuated connected to the different windings of said power driven extensible and retractable antenna means and mounted adjacent said power driven extensible and retractable antenna means and actuated by extreme positions thereof, relay operated switching means connected to one of the separate switching means of'tlie limit switching means and to the source of power, coilmeans for actuating said relay operated switching means,

conductive means connecting said coil means to said energizing switch so that when the latter is actuated to energize the radio apparatus, the power'driven' extensible and retractable antenna means will be automatically extended to one limit position and when it is actuated to deenergize the radio apparatus the power driven extensible and retractable antenna means will be retracted to another'limit position.

2. In radio apparatus having a source of electrical power and an energizing switch connected to said source of power and radio'apparatus to control the latter, power 'drivenextensible and retractable antenna means connected to said radio apparatus, a plurality of separate switching means connected to said power driven extensible and retractable antenna means and to the energizing switch and mounted adjacent said power driven extensible and re tractable antenna means and actuated by the position thereof, further switching means connected to at least one of the separate switching means connected to the power driven extensible and retractable antenna means and to the source of power energizable means for actuating said further switching means connected to said energizing switch so that when the latter is actuated toenergize the radio apparatus, the power driven extensible and retractable antenna means will be automatically extended and when it is actuated't o deenergize the radio apparatus, a

the power driven extensible and retractable antenna means will be automatically retracted, and manually operable means engageable with said further switching means to operate the same and to cause operation .of the power driven extensible and retractable antenna means when theradio apparatus is energized;

3. In radio apparatus having a source of electrical power and an energizing switch connected to said source of power and radio apparatus to control the latter, power driven extensible and retractable antenna means connected to said radio apparatus extending and retracting said antenna-plurality of separate switching means alternat-ively closed and connected to said power driven extensible and retractable antenna means and mounted adjacent the same and actuated by extreme positions thereof, further switching'means' connected to at least one of'the plurality of separate switching means and tow the source of-p'ower, energizable means for actuating said tion of said power driven extensible and retractable antenna means.

4. In radio receiving apparatus having a source of electrical power and an energizing switch for turning the radio receiving apparatus on and ofi, a power driven extensible antenna connected to said receiving apparatus said power driven extensible antenna having a plurality of windings to extend or retract the antenna, a plurality of separate switching means independently connected to said windings and mounted adjacent the power driven extensible antenna to complete a circuit to alternate windings, further switching means connected to said plurality of separate switching means and to the source of power to control the winding energization of the power driven antenna means, actuating means for the further switching means and conductive means connecting said energizing switch, said actuating means and said source of power to control the actuating means and in turn.- the power driven extensible antenna means when the radio reeeiving apparatus is turned on or 0115.

References Cited in the file of this patent UNITED STATES PATENTS 1,534,750 Vernon Apr. 21, 1925 2,233,222 Paton Feb. 25, 1914 2,272,213 Lear Feb. 10, 1942 2,329,329 Brach et a1. Sept. 14, 1943 2,384,631 Mace Sept. 11, 1945 2,695,382 Wheatley et al. Nov. 23, 1954 

